The invention relates to an auxiliary tool for assembling a scrubber; in particular, the invention relates to an auxiliary tool that can readily assemble the scrubber with ease and precision.
In semiconductor processing, a wafer surface is usually required to be cleaned. By means of brush cleaning, spray cleaning, and ultrasonic cleaning, undesired substance remaining on the wafer surface can be eliminated.
Cleaning equipment, such as a scrubber, is shown in FIG. 1a and FIG. 1b. A wafer 1 is placed on wafer support pins 4 of a spin chuck 3 by a robot 2. Each wafer support pin 4 is provided with a stepped portion, as shown in FIG. 1a, to support the wafer 1. The distance between the wafer support pins 4 is large enough for the robot 2 to access. The spin chuck 3 is connected to a shaft 5. A shaft pin 6, as shown in FIG. 1b, is disposed at the shaft 5 and used to position the spin chuck 3 and the shaft 5.
Referring to FIG. 1b, the shaft 5 is disposed inside a motor 7 in a rotatable manner.
The motor 7 rotates the spin chuck 3. The other end of the shaft 5 is connected with a disk 8 by means of a fixing or mounting part 10. The disk 8 is provided with a notch 9. A cylinder 11, disposed on unillustrated equipment, abuts the notch 9 to stop the disk 8.
FIG. 2a shows a relationship between the disk 8 and sensors disposed on the surrounding equipment. A sensor 13 is disposed at the edge of the disk 8. A sensor 12, corresponding to the sensor 13, is disposed at the surrounding equipment. The rotation number of the disk 8 is detected by the sensors 12, 13 to determine whether the cleaning process is finished. FIG. 2b is a top view of the spin chuck 3. The wafer 1, shown with a dotted line, is placed on the wafer support pins 4. FIG. 2b also shows a relationship between the robot 2 and the wafer support pins 4 when the robot 2 enters the spin chuck 3.
Part of the scrubber is described as above. Since the motor 7 rotates at high speed over a long period, it is relatively easily damaged and must be replaced. However, replacement of the motor is time-consuming. In addition, when the disk 8 is mounted to the shaft 5 during the replacement of the motor 7, the distance and the angle between the disk 8 and the shaft 5 is extremely limited.
If the distance between disk 8 and the shaft 5 is not precise, the disk 8 can interfere with the sensor 12 of the surrounding equipment, or the motor 7 cannot be assembled into the scrubber. If the angle between disk 8 and the shaft 5 is not precise, the position at which the robot 2 enters the spin chuck 3 may become inaccurate enough that the robot 2 may collide with the wafer support pins 4 of the spin chuck 3. As a result, it may require a significant amount of time to attach the disk 8 to the shaft 5 properly.